Mail Issue

Whenever I send an e-mail whether I am using NeoMail, Horde, SquirrelMail or just Outlook the message's FROM field always shows up <myusername@machine.hostingcompaniesdomain.com> on behalf of <myemailbox@mydomain.com>.

Whenever I receive a message the FROM field always shows <myusername@machine.hostingcompaniesdomain.com> on behalf of <whomever it was sent by@domain.com>.

In WHM > Service Configuration > Exim Configuration Editor, there is the tickable option:

"Always set the Sender: header when the sender is changed from the actual sender. (Unchecking this will stop "On behalf of" data in Microsoft(R) Outlook, but may limit your ability to track abuse of the mail system.)"

From what I understand (gained from limited experience and therefore maybe wrong), Outlook will add the "On behalf of" malarky if the Sender: header is present in mail and differs from the From: header. I believe that this will only happen when viewing mail through Outlook.

In short, unchecking the above mentioned option should stop this, but I'm not sure if that's a good idea (still trying to figure this out myself).